A colony of fully pedigreed Monodelphis domestica has been used to investigate the maternal-fetal relationship in this unique marsupial species. To determine how immunity is transferred from mothers to young in M. domestica, we hyperimmunized females with sheep red blood cells (SRBC) before and during gestation. Offspring from these females were collected at various times after birth, and saline extracts of the neonates were assayed for hemolysins against SRBC. Antibodies were present in extracts of newborn that had been allowed to suckle their mothers; none were detected in extracts of infants that were not allowed to suckle. Antibodies were present in the milk of immunized mothers, but were not detected in the milk of nonimmunized mothers. The titer of antibodies in the extracts of newborns generally increased proportionately to the time that the newborn had been allowed to suckle. We conclude that the transfer of passive immunity from mothers of M. domestica to their offspring occurs primarily via the milk.

No abstract

No abstract

Three new blood group systems, called "T," "U," and "V," have been identified in the rhesus monkey (Macaca mulatta). Each system consists of a single antigenic factor (blood group) detected by a monospecific alloimmune reagent that agglutinates erythrocytes. The antisera that detect these blood groups were obtained following a series of alloimmunizations and absorption fractionizations of the resulting antisera to produce operationally monospecific typing reagents. Analyses of family data indicated that each blood group was controlled by an autosomal dominant gene and that each system was independent of previously defined systems. With the addition of these new blood groups, we can identify 16 different blood group systems and well over one hundred million possible phenotypes in this species.

Summary. We describe a new antiserum that has the unique ability to distinguish homozygous from heterozygous genotypes in the G blood group system of rhesus monkeys. With this new typing serum (reagent), all 10 possible genotypes in this system can be distinguished and the utility of blood typing for genetic studies has been greatly increased.